Thank you so much. Now we turn to that manhunt, the 29-year-old giving chase to the u.S. Security establishment. Edward snowden who made all those top secret documents public emerged for a shadowy moment before disappearing again. He even hinted there may be more secrets to come. Here's abc's chief investigative correspondent, brian ross. Reporter: Today snowden made it clear he is still in hong kong telling the post it is here that he wants to make his last stand to reveal what he called the criminal national of the u.S. Government surveillance programs and targets worldwide. Snowden may be holding a lot more secrets. His last post was at the nsa, the national security agency facility in hawaii that is a hub for american spying and computer hacking on china and north korea as well as hong kong. If he makes public the names of government officials and others who are targets it could be far more devastating than what he has done so far. That's the $64,000 question of we don't know who the targets are. If that comes out then there will be serious damage to national security. Reporter: In congress today the head of the nsa, general keith alexander said snowden already hurt the u.S. Great harm has already been done by opening this up. Our security is jeopardized. Reporter: Alexander and others said the 29-year-old snowden had been dishonest about his background and his claims to the guardian newspaper that u.S. Citizens are being wire tapped. I sitting at my desk have the authorities to wire tap anyone from you or your accountant to a federal judge to even the present the if I had a personal e-mail. False. I know of no way to do that. Reporter: Even so the head of the nsa acknowledged he was stunned that a 29-year-old analyst who dropped out of high school in his sophomore year could have access to so many top secret documents. I have grave concerns over that. The access that he had, the process that we did. Reporter: But the general strongly defended the nsa's secret programs as legal, necessary and responsible he said, for stopping dozens of terrorist events in the u.S. And abroad. Brian ross reporting in again tonight. Thank you, brian.

This transcript has been automatically generated and may not be 100% accurate.

{"id":19386477,"title":"Edward Snowden Makes Stand in Hong Kong","duration":"2:20","description":"Alleged NSA Leaker Says He Has No Plans to 'Hide From Justice'.","url":"/WNT/video/edward-snowden-makes-stand-hong-kong-19386477","section":"WNT","mediaType":"default"}